Within the scope of use of high electrical voltages, for example in the field of electronics for automotive engineering, there is a need to galvanically separate individual electronic circuits from one another, i.e., to keep different circuits at different direct voltage potentials. At the same time, data must be exchanged between these circuits at high speed. Data rates typically range from a few hundred kilobits/second to 50-100 megabits/second for differences in potential between a few hundred volts and several kilovolts.
A potential-free data transmission device between a master level and at least one monolithically integrated sublevel is discussed in DE 42 05 241 C2, having a Hall voltmeter which, via the magnetic field of a coupling loop which is spatially closely connected to, in particular integrated into, the sublevel, evaluates as data information the particular current of a low-resistance, low-inductance two-wire bus line which is connected to the coupling loop.